<template>
  <div class="about">
    <h1>{{ msg }}</h1>
    <button @click="set">set</button>
    <button @click="a">alert</button>
  </div>
</template>

<script setup>
import { ref,  reactive } from 'vue'
const msg = ref('hellow world')
function set () {
    msg.value = 'asdf'
}
const a = () => {
    alert(msg.value)
}
</script>

<style>
.about {
  font-size: 2em;
  text-align: center;
}
</style>
